This invention relates to reservoirs for rod-like articles, particularly articles of the tobacco industry such as cigarette filter rods or cigarettes, in which the articles are stored in multi-layer stack formation.
According to one aspect of the invention a reservoir for rod-like articles includes means defining a variable capacity storage region including a movable end wall which is movable towards and away from a stationary end wall to vary the capacity of the region, extendible guide means movable with the movable end wall and spaced therefrom to define therewith a passage for rod-like articles, said guide means being extendible from a position intermediate said stationary wall in which position said movable end wall and said stationary wall define a substantially vertical path extending from an upper inlet to a lower outlet and which path includes said passage, said guide means when extended into said storage region defining an extended path between said inlet and said outlet including an upper portion extending from an upper part of said vertical path to said movable end wall and a lower portion extending from said movable end wall to a lower part of said vertical path. Preferably said upper and lower portions are each arranged to support multi-layer streams of rod-like articles. Preferably the stream on said lower portion is significantly deeper than that on the upper portion, i.e. the extendible guide means projects into the storage region nearer to the top of the storage region than to the bottom.
Preferably the bottom of the storage region is defined by a movable conveyor for supporting and conveying rod-like articles. This movable conveyor and the movable end wall preferably move at the same rate when the end wall is moving towards the stationary wall, i.e. when the capacity of the storage region is being reduced, thereby ensuring that no voids are created in the storage region.
The extendible guide means may comprise drivable conveyor means, so that it may convey a stream of rod-like articles in the storage region towards the movable end wall. Where the guide means comprises an extendible band, parts of the band not projected into the storage region may be stored in vertical alignment with, e.g. above or below, the storage region.
According to a further aspect of the invention a reservoir for rod-like articles comprises a substantially linear variable capacity storage region, an entrance for articles at one end, an exit for articles at the other end, means for storing articles in a relatively deep stack in said storage region, movable boundary means for varying the capacity of said storage region by varying the length of said storing means, and means for varying the operative length of at least one article conveyor extending at least part of the distance between said entrance and said exit.
In a preferred arrangement the movable boundary means comprises means arranged at a downstream end of said storing means and includes means for conveying articles towards said exit. Such conveying means may comprise endless band conveyor means having guide means movable with said boundary means.
The boundary means preferably includes or at least defines means for passing articles between the entrance and the exit. Preferably the boundary means includes means for impeding passage of articles delivered from the storing means. Such impeding means may comprise a conveyor path along which articles may pass only when conveyor means associated with the path is operated, or may comprise a movable gate. Where the impeding means comprises conveyor means this may include an elevator and/or means for displacing part of the conveyor means to block or reduce the width of a path for articles.
The boundary means may be reversibly movable between said entrance and said exit and may incorporate conveyor means capable of moving articles towards an exit. Where the storage region extends substantially horizontally the boundary means may be movable with a floor conveyor for the storage region; alternatively the boundary means may be movable independently of such a floor conveyor. The boundary means may be cyclically reciprocable in order to encourage through-flow in the reservoir, particularly under conditions where the rates of supply and demand are substantially matched. Through-flow could also be encouraged by inclining the reservoir slightly.
The reservoir may include a variable length conveyor extending from the boundary means to the exit of the reservoir. Alternatively, or additionally, variable length conveyor means may extend from the entrance of the reservoir to the boundary means. The operative run of the or each variable length conveyor may be supported by means of extendible support means. Such means may comprise spaced elements which are movable from retracted positions out of the path of the leading end of the conveyor as it advances but movable by cam means (operated by means movable with said leading end) into an operative position to support the conveyor after the leading end has passed. In a preferred arrangement the spaced elements comprise horizontal support rollers each connected to a vertical pivot so as to be displaceable about a vertical axis from a position parallel to and at one side of the conveyor and into positions transverse and immediately beneath the operative run of the conveyor. Cam means is provided to move said support rollers into their operative positions on extension of the variable length conveyor and to return the rollers to retracted positions on retraction of the conveyor.
Where the extendible guide means of the first aspect of the invention comprises an extendible band the operative run of the latter may be supported by extendible support means in a manner similar to that mentioned in the previous paragraph.
A reservoir according to the invention is particularly conveniently usable for buffer storage of cigarette filter rods delivered pneumatically to a filter cigarette assembly machine (i.e. a filter attachment machine) prior to utilisation of the rods by the machine. Thus the reservoir may be closely associated with a filter cigarette attachment machine and may, for example, extend horizontally above part of it.